<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>文本格式化</title>
</head>
<body>
    <b>This text is bold</b>
    <br/>
    <strong>This text is strong</strong>
    <br/>
    <big>This text is big</big>
    <br/>
    <em>This text is emphasized</em>
    <br/>
    <i>This text is italic</i>
    <br/>
    <small>This text is small</small>
    <br/>
    This text contains
    <sub>subscript</sub>
    <br/>
    This text contains
    <sup>superscript</sup>
</body>
</html>